Drive device

ABSTRACT

Drive device ( 10 ), in particular to raise and lower windows in a motor vehicle, with an electric motor ( 12 ) featuring an armature shaft ( 16 ), a printed circuit board ( 32 ) projecting out of an electronic housing ( 36 ), a gearbox housing ( 18 ) and several guides ( 44 ) to spatially fix the printed circuit board ( 32 ) in the gearbox housing ( 18 ), whereby different guides ( 44 ) interact with the printed circuit board ( 32 ) for different printed circuit boards ( 32 ) with different widths ( 62 ) and/or lengths and/or with different distances ( 66 ) to the armature shaft

STATE OF THE ART

The invention concerns a drive device in particular to raise and lowerwindows in a motor vehicle in accordance with the species of theindependent claim.

Numerous drive devices for this purpose are known, for example from DE200 04 338 A1. The drive device disclosed in this document features anelectric motor with a gearbox housing, in which a plug-in module can beinserted. The plug-in module features a front surface with a connectorfor the motor power supply and a printed circuit board on whichelectronic components are arranged. A SMD Hall sensor is arranged on anarrow finger of the printed circuit board and in an assembled state thesensor interacts with a ring magnet of the armature shaft. In this case,only a guide provided with a seal on the front side of the plug-inmodule far away from the armature shaft is used to precisely positionthe Hall sensor.

If a guide is now formed for the printed circuit board finger tosecurely position the Hall sensor in the gearbox housing (in order toavoid deviations from the target distance of the Hall sensor duringassembly or in the case of vehicle shocks, for example), this guideinterferes when using other types of printed circuit boards. For otherapplications, for example with Hall sensors integrated on an ASIC, it isdesirable that a wider printed circuit board having a different distanceto the armature shaft can be plugged into the same gearbox housing. Indoing this, these two printed circuit boards collide with the guidesformed in the gearbox housing for the first printed circuit boardthereby making it impossible to use same gearbox housing for differentprinted circuit boards.

ADVANTAGES OF THE INVENTION

The drive device in accordance with the invention with the feature ofthe main claim has the advantage that universal gearbox housings andelectronic housings are created, which make assembly possible withdifferently formed printed circuit boards. There are enormous advantagesto a modular production technique that is thereby made possible. Themore complex larger housing parts can be produced in very large unitnumbers. The associated simpler components, such as the electronichousing cover, can be adapted very simply to different printed circuitboards. The design of the guides in accordance with the invention inparticular permits secure positioning of different printed circuitboards with different distances to the armature shaft.

Advantageous further developments of the drive device in accordance withthe invention are made possible by the features listed in thesub-claims. If the guides are at least partially embodied as limit stopsin the gearbox housing, on which the printed circuit board abuts withits side facing towards or facing away from the armature shaft, thedistance of the Hall sensor to the magnet of the armature shaft isclearly fixed as a result. This permits a precise determination ofposition with low interfering signals.

If the guides in the gearbox housing are arranged in such a way thatthey interact with the axial edge areas of the printed circuit board,varying widths of printed circuit boards can be guided on axiallydifferent edge areas, whereby a collision of the one printed circuitboard with the guides of the other printed circuit board can be avoided.

It is especially favorable to form one guide as a land on the electronichousing on which the printed circuit board rests since this land, inconnection with the gearbox housing wall, assumes the function of alimit stop to fix a maximum distance of the printed circuit board fromthe armature shaft without such a limit stop having to be formed on thegearbox housing for this printed circuit board. As a result, this guidedesigned as a land does not collide with the guides arranged on thegearbox housing, which interact with the axial edge areas of the printedcircuit board. The land abuts the printed circuit board in particular inthe axially middle area and supports it against the gearbox housingwall.

It is especially simple in terms of manufacturing technology to form theland as one piece with the electronic housing, e.g., by means of aninjection molding process. It is even more favorable to always designthe electronic housing to be identical and merely form a land on thecover of the electronic housing in accordance with the desired printedcircuit board.

If the printed circuit board is permanently connected to the land, e.g.,with a clip or locking connection, this facilitates assembly of theelectronic housing since displacement of the printed circuit boardvis-à-vis the land is prevented. In addition, such a connection betweenthe printed circuit board and the land permits a separate design of theland detached from the electronic housing.

It is advantageous to form the opening in the gearbox housing in such away that the land can support itself on the one side on the gearboxhousing during insertion and in an assembled state, and, on the otherhand, the printed circuit board presses against a limit stop, whichprescribes the minimum distance of the printed circuit board to thearmature shaft.

If the land projects beyond the printed circuit board in thelongitudinal direction, this free end of the land can support itselfwith its front side on another guide in the gearbox housing. The shorterdesign of the printed circuit board finger permits more effectivematerial utilization during manufacture of the printed circuit board. Ifthe electronic housing is embodied as a separate housing, it can beconnected in a simple manner with the gearbox housing as a plug-inmodule. In this connection, the electronic housing features only onesmall opening from which the different printed circuit boards project.This relatively small opening between the electronic housing and thegearbox housing can be sealed against water and dirt in a relativelysimple and effective manner.

In addition, guides can also be formed on a brush holder, which can bemounted axially to the armature shaft as an approximately annularcomponent. Since the brush holder lies in the direct spatial vicinity ofthe magnet of the armature shaft, these guides also afford reliablespatial fixing of the Hall sensors vis-à-vis the ring magnet.

It can be advantageous in terms of manufacturing technology to designthe guides as grooves in the gearbox housing or in the brush holder intowhich the axial edge areas of the printed circuit board are plugged.

The compatibility of the gearbox housing and the electronic housing withthe various printed circuit boards permits the use of both SMD Hallsensors with relatively low printed circuit board space requirements andHall sensors that are integrated into a ASIC and require moreconstruction space on the printed circuit board. As a result, the designof the drive device is independent of future electronic developments inthis area.

Due to the parallel arrangement of the printed circuit board with thearmature shaft, the Hall sensor can be fastened directly on the printedcircuit board with or without ASIC, to some extent by means of fullyautomatic SMD processes, without a special holder being required for theHall sensors.

If a worm is formed on the armature shaft, which drives a worm gear withan output gear, a compact adjusting drive with exact determination ofposition is thereby created, such as is used for window lifters in motorvehicles, for example.

DRAWINGS

Exemplary embodiments of the invention area depicted in the drawings andexplained in more detail in the following description:

FIG. 1 a shows a schematic representation of a drive device inaccordance with the invention;

FIG. 1 b shows an electronic plug-in module for the drive device inaccordance with FIG. 1 a;

FIG. 1 c shows another electronic plug-in module with a differentprinted circuit board;

FIGS. 1 d and 1 e show two sections through the plug-in module inaccordance with Lines d—d and e-e;

FIGS. 2 a and 2 b show two partial sections in accordance with LineII—II of the two different inserted printed circuit boards according toFIGS. 1 b and 1 c; and

FIGS. 3 a and 3 b show two sections of the two inserted plug-in modulesin accordance with Line III—III.

DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

FIG. 1 a depicts a drive device 10 for a window lifter, which featuresan electric motor 12 with a pole casing 14 from which an armature shaft16 projects into a gearbox housing 18. Arranged on the armature shaft 16is a worm 20, which meshes with a driven gear 22 and transmits the forcevia an output gear 26 positioned on its axis 24 to the window liftingmechanics (not shown in greater detail). To determine the position of anadjustable part, a ring magnet 28 is arranged on the armature shaft 16in the area of the gearbox housing 18, which ring magnet interacts withHall sensors 30, which are arranged on a printed circuit board 32 of anelectronic plug-in module 34. FIG. 1 b shows such a plug-in module 34,which is embodied as a separate electronic housing 36 from which a partof the printed circuit board 32 projects as a plug-in finger. Forassembly, the plug-in module 34 is inserted into the gearbox housing 18with the plug-in finger in accordance with arrow direction 40 andpermanently connected with the gearbox housing 18 by means of lockingelements 42. For exact spatially positioning, the printed circuit board32 is guided by means of guides 44 during plug-in and fixed in anassembled state. In the exemplary embodiment the guides 44 are formed aslimit stops 68, 76, 77, 82, 83 in the gearbox housing 18 and formed onan annular brush holder 48 mounted axially to the armature shaft 16.Depending upon the design of the drive device 10, the borders betweenthe individual housing parts can also be embodied differently so that,e.g., the ring magnet 28 is also arranged in the area of an extendedpole casing 14 or a separate intermediate piece 50—which is essentiallyformed by the brush holder 48 for example—between the gearbox housing 18and the pole casing 14. The guides 44 are embodied for example to be onepiece with the corresponding housing parts 18, 14, 50, 48 preferably bymeans of an injection molding process. One part of the guides 44 isembodied as a groove 52 in a housing wall. In FIGS. 1 b and 1 d, a land60 is formed on the electronic housing 36, which features the same width62 as the printed circuit board 32 and is connected to said circuitboard by means of a clip connection 64. The Hall sensors 30 are attachedvery flatly to the printed circuit board 32 using SMD technology so thatthe printed circuit board 32 is positioned at a short distance 66 to thearmature shaft 16 tangential to the ring magnet 28.

FIG. 2 a shows a section through the plugged-in printed circuit board 32of the plug-in module 34 from FIG. 1 b. With its side 70 facing the ringmagnet 28, the printed circuit board 32 is adjacent in the area 72axially facing away from the electric motor 12 to a limit stop 68 of thegearbox housing 18, which determines the minimum distance of the printedcircuit board 32 to the ring magnet 28. The guide 44 formed as a land 60is adjacent to the printed circuit board 32 on its side 74 facing awayfrom the ring magnet 28 and presses the printed circuit board 32 againstthe limit stop 68. With the other side, the land 60 supports itself onthe gearbox housing 18 and thereby forms a limit stop for the printedcircuit board 32, which corresponds to the maximum distance of theprinted circuit board 32 to the ring magnet 28.

FIG. 1 c shows another plug-in module 34, whose electronic housing 36 isformed essentially the same as that in FIG. 1 b. However, the plug-inmodule 34 is equipped with a different printed circuit board 32, whichfeatures a greater width 62 on its area projecting out the electronichousing 36 in order to accommodate an ASIC component 80 for example. TheASIC component contains a complete microprocessor for controlelectronics and is positioned on the printed circuit board 32 in such away that the Hall sensors 30 integrated into the ASIC 80 are positioneddirectly across from the ring magnet 28 in a plugged-in state. Due tothe larger construction height of the ASIC 80, the distance between theprinted circuit board 32 and the armature shaft 16 is greater than inthe case of the SMD Hall sensors 30 as can be seen in the illustrationin FIG. 2 b. The limits stop 68 for the printed circuit board 32 withthe SMD Hall sensors 30 remains unused in this arrangement, and thewider printed circuit board 32 with the ASIC 80, on the other hand, isspatially fixed in its distance to the ring magnet 28 by two limit stops76 and 77 on the gearbox housing 18 or the brush holder 48. In thisarrangement, the printed circuit board 32 is adjacent with its area 78axially facing the electric motor 12 to its side 70 facing the ringmagnet 28 at the limit stop 76 to determine the minimum distance 66, andis pressed against the limit stop 76 by the limit stop 77, which abutsthe side 74 facing away from the ring magnet 28. In the process, thelimit stop 77 assumes the function of the land 60 in the case of thenarrower printed circuit board 32. As a result, the plug-in module 34does not have a land 60 in the case of the wide printed circuit board 32with the ASIC 80. On the other hand, the limit stops 76 and 77 have nofunction in the case of the plug-in module 34 with the narrow printedcircuit board 32 in FIG. 2 a.

FIG. 3 a shows a section with a mounted plug-in module 34 with a narrowprinted circuit board 32 in accordance with FIG. 2 a. The printedcircuit board 32 in this case just projects out of the electronichousing 36 into the gearbox housing 18, whereby the printed circuitboard 32 is arranged parallel to the armature shaft 16, or tangentiallyto the ring magnet 28. The limit stop 68 on the side of the printedcircuit board 32 facing away from the electric motor 12 prescribes theminimum distance to the armature shaft 16, and the land 60, which isembodied here as one piece with the electronic housing 36, presses theprinted circuit board 32 against the limit stop 68, whereby the land 60is supported on the wall of the gearbox housing 18. In this connection,the gearbox housing 18 features a cover 37, with which the land 60 isarranged approximately in a plane. Due to the low construction space ofthe SMD Hall sensors 30, the printed circuit board 32 does not extend upto the limit stops 82, 83 or the groove 52, which are arranged in thearea of the free end 33 of the printed circuit board 32 on the gearboxhousing 18.

FIG. 3 b correspondingly depicts a section through the wide printedcircuit board 32 with the ASIC 80. This printed circuit board 32 isspatially fixed by the two limit stops 76, 77, which guide the printedcircuit board 32 at the area facing the electric motor 12. As a result,the cover 37 of the gearbox housing 18 does not have a land 60. Theprinted circuit board 32 extends beyond the ring magnet 28 and is alsoguided here at its free end 33 by the two limit stops 82 and 83.Alternatively, the two limit stops 82, 83 can also be formed as a groove52 in the gearbox housing in the axial direction, which can accommodatethe free end 33 of the printed circuit board 32 over its entire width.The additional fixing of the printed circuit board 32 at its free end 33prevents the distance between the Hall sensors 30 and the ring magnet 28from being altered, e.g., by outside shocks.

The land 60 is embodied to be longer than the free end 33 of the printedcircuit board in an alternative exemplary embodiment with a plug-inmodule 34 with the narrow printed circuit board 32. This extension 60′of the land also makes additional fixing at the limit stops 82 and 83 orthe groove 52 possible. The extension 60′ of the land 60 is formed inthis case in such a way that its end 61 has exactly the same distance 66to the armature shaft 16 as the printed circuit board in FIG. 3 b thatis embodied to be longer. In this connection, the extension 60′ has thesame thickness 86 at its end 61 as the standardized thickness 86 of thetwo printed circuit boards 32. As a result, the shorter printed circuitboard 32 is also additionally fixed at its free end 33 by the extension60′ in order to guarantee a constant distance 66 between the printedcircuit board 32 and the armature shaft 16.

In another exemplary embodiment, the plug-in module 34 is not embodiedwith a separate electronic housing 36, but is completely inserted intothe gearbox housing 18 so that, e.g., a front side of the plug-in module34 simultaneously constitutes a cover for the gearbox housing 18. Inthis case, the printed circuit board 32 is not formed to be L-shaped,for example, as in FIGS. 1 b or 1 c, but formed as a whole asapproximately rectangular, whereby one side of the rectangle correspondsto the width 62.

The device in accordance with the invention is not limited to the twodescribed plug-in modules, but includes any combination of differentplug-in modules with different printed circuit boards 32 with a singlegearbox housing. In the process, the land 60 can also be embodied as aseparate component, which is fastened to the rear side of the printedcircuit board 32, e.g., glued or clipped on.

1. Drive device (10), in particular to raise and lower windows in amotor vehicle, and for use with a printed circuit board (32) projectingout of an electronic housing (36), the device comprising an electricmotor (12) featuring an armature shaft (16), a gearbox housing (18) andguides (44) configured for interaction with varying printed circuitboards to spatially fix a selected printed circuit board (32) in thegearbox housing (18), wherein different guides (44) interact with theprinted circuit board (32) for different printed circuit boards (32)with different widths (62) and/or lengths and/or with differentdistances (66) to the armature shaft (16).
 2. Drive device (10)according to claim 1, characterized in that at least one portion of theguides (44) is embodied as limit stops (44, 68, 76, 77, 82, 83, 52) onthe gearbox housing (18), on which the printed circuit board (32) abutswith its side (70, 74) facing towards or facing away from the armatureshaft (16) to fix a minimum or maximum distance (66) to the armatureshaft (16).
 3. Drive device (10) according to claim 1, characterized inthat at least one portion of the guides (44) is arranged in the gearboxhousing (18) in such a way that the printed circuit board (32) abutsthese guides (44) on their areas (78, 72) axially facing towards andfacing away from the electric motor (12).
 4. Drive device (10) accordingto claim 1, characterized in that at least one guide (44, 60, 60′),particularly for a printed circuit board (32) with a small width (62),is embodied as a land (60, 60′), which can be plugged into the gearboxhousing (18) with the printed circuit board (32).
 5. Drive device (10)according to claim 4, characterized in that the land (60, 60′) is formedon the electronic housing (36), particularly as one piece on its cover(37).
 6. Drive device (10) according to claim 4, characterized in thatthe printed circuit board (32) is permanently connected to the land (60,60′), particularly by means of a clip connection (64).
 7. Drive device(10) according to claim 4, characterized in that the land (60, 60′) issupported on its side (58) facing away from the printed circuit board(32) on the gearbox housing (18).
 8. Drive device (10) according toclaim 4, characterized in that the land (60, 60′) is embodied to belonger than the printed circuit board (32) and with its free end (61)abuts guides (44), which are arranged as limit stops (82, 83, 52) on thegearbox housing (18).
 9. Drive device (10) according to claim 1,characterized in that the electronic housing (36) is embodied to beseparable and can be connected to the gearbox housing (18), particularlyby means of locking elements (42).
 10. Drive device (10) according toclaim 1, characterized in that a brush holder (48) can be mountedaxially to the armature shaft (16), on which brush holder particularlyguides (44) for the printed circuit board (32) are formed.
 11. Drivedevice (10) according to claim 1, characterized in that the guides (44)are at least partially embodied as grooves (52).
 12. Drive device (10)according to claim 1, characterized in that both a printed circuit board(32) with Hall sensors (30) integrated into an ASIC (80) and a printedcircuit board (32) directly equipped with Hall sensors (30) can be fixedon both sides by means of guides (44).
 13. Drive device (10) accordingto claim 1, characterized in that the printed circuit board (32) isarranged parallel to the armature shaft (16), in particular tangentialto a magnet (28) fastened to this shaft.
 14. Drive device (10) accordingto claim 1, characterized in that the armature shaft (16) features aworm (20), which meshes with a worm wheel (22), on whose axis (24) anoutput gear (24) is arranged.
 15. A method of providing a drive deviceto raise and lower windows in a motor vehicle, the method comprising:providing a device with an electric motor having an armature shaft and agearbox housing; providing the device with guides configured forinteraction with varying printed circuit boards to spatially fix aselected printed circuit board in the gearbox housing, wherein differentguides interact with different printed circuit boards with differentwidths and/or lengths and/or with different distances to the armatureshaft; and plugging into the device a selected printed circuit boardprojecting out of an electronic housing, such that the selected printedcircuit board is fixed in the gearbox housing by the guides.
 16. Amethod according to claim 15, wherein providing the guides includesproviding on the gearbox housing limit stops which abut the printedcircuit board.
 17. A method according to claim 16 wherein the limitstops abut the side of the printed circuit board facing towards orfacing away from the armature shaft to fix a minimum or maximum distanceto the armature shaft.
 18. A method according to claim 17 wherein atleast one portion of the guides is arranged in the gearbox housing insuch a way that the printed circuit board abuts the guides on areasaxially facing towards and facing away from the electric motor.
 19. Amethod according to claim 18 wherein at least one guide, particularlyfor a printed circuit board with a small width, is embodied as a landwhich can be plugged into the gearbox housing with the printed circuitboard.
 20. A method according to claim 19 wherein the land is formed onthe electronic housing, particularly as one piece on its cover.
 21. Amethod according to claim 20 wherein the printed circuit board ispermanently connected to the land, particularly by means of a clipconnection.
 22. A method according to claim 21 wherein the land issupported on its side facing away from the printed circuit board on thegearbox housing.
 23. A method according to claim 22 wherein the land isembodied to be longer than the printed circuit board and with its freeend abuts guides, which are arranged as limit stops on the gearboxhousing.
 24. A method according to claim 23 wherein the electronichousing is embodied to be separable and can be connected to the gearboxhousing, particularly by means of locking elements.
 25. A methodaccording to claim 24 wherein a brush holder can be mounted axially tothe armature shaft, on which brush holder particularly guides for theprinted circuit board are formed.
 26. A method according to claim 25wherein the guides are at least partially embodied as grooves.
 27. Amethod according to claim 26 wherein both a printed circuit board withHall sensors integrated into an ASIC and a printed circuit boarddirectly equipped with Hall sensors can be fixed on both sides by meansof guides.
 28. A method according to claim 27 wherein the printedcircuit board is arranged parallel to the armature shaft, in particulartangential to a magnet fastened to this shaft.
 29. A method according toclaim 28 wherein the armature shaft features a worm, which meshes with aworm wheel, on whose axis an output gear is arranged.